ES2250795T3 - PROCEDURE AND APPLIANCE FOR THE SELECTION AND FEEDING OF PRODUCTS. - Google Patents

Abstract

Procedure for the selection and feeding of products to blister packs or containers, from a main hopper (4) full of products (2), the procedure being characterized in that it includes the following: provide an auxiliary hopper (3) full of unselected products ( 2); feeding said main hopper (4) with products obtained from said auxiliary hopper (3) through selection means (6) that retain the products of unequal size (20); extracting from said selection means (6) the products of unequal size (20), which are retained therein, in order to restore a regular flow of product feed; feeding said containers with products of similar size (2 *) contained in said main hopper (4).

Description

Procedure and apparatus for selection and product feed.

The present invention relates to automatic packaging of various products, in particular of drugs, but preferably food or products similar to drugs, such as candy, chewing gum and Similar. These products can be packaged in blister packs, although they can also be packaged in other types of packages powered by devices similar to those used to fill blister packs.

In particular, the present invention relates to a procedure for the selection and feeding of said products, and to an apparatus capable of carrying out the present process.

Currently used packages, usually referred to as "blister packs", or similar containers, such as bottles, small boxes and the like, are filled in a filling station, where at least one product or each bottle is inserted into each blister pack or box is filled with a series of
products.

Next, reference is made with more frequency only to the packing procedure in blisters However, it should be understood that the invention, as well as all the considerations that are made hereinafter memory, mainly apply also to the packaging of products in bottles or boxes or other similar containers, with the proviso that the procedure and feeding apparatus used are the same or very similar.

The known devices for filling the Blister packs, according to different techniques, are particularly efficient and reliable for high products quality, such as pharmaceuticals or products similar to pharmacists, that is, for products whose Dimensions are very homogeneous.

However, the feeding of products that have substantially different dimensions, may result particularly difficult.

Typically, package filling devices blister known to those skilled in the art, and often also similar devices for filling bottles and boxes, include a plurality of feed channels, at along which products are transported in rows up to blister packs, for example prepared by forming a band, or to the bottles or boxes.

The lower ends of the channels enter contact with the surface of the band, feeding the products to the inside of the respective blister packs, as pass under them.

The channels are connected in parallel with a feeding device, for example a hopper vibratory, within which products are collected in large quantities.

The vibrations of the hopper, amplitude and preset frequencies, facilitate the systematic introduction of Products in each channel.

As indicated above, in the case of high quality products, in which all fit perfectly to the required size, all the products passes freely through the channels and enters the packages blister that at each moment are below, without causing traffic jams within the channels and allowing a flow substantially continuous and regular in them.

In the case of lower quality products, for example for food use (chewing gum, candies, etc.), the hopper may contain products that do not fit perfectly to the nominal size and can cause jams and obstacles in the channels, usually in their entrance area. This fact negatively affects the flow of products that are being fed to the containers.

Traffic jams and obstacles can result caused by products whose dimensions are not compatible with the sections of the channels, or because the products are hooked each other thus forming groups of products.

Typically, products are introduced into large quantities in the hopper after a selection or are selected as they are fed to the containers. However, of generally only one hopper is provided and the selection causes a temporary interruption of the flow of products. The product flow interruption may cause missing products in the containers or a delay in the operation of packing Sometimes, it may even require you to stop the machine, resulting in all the above in a time outside of considerable service. From US Patent No. B1-6345487 are known a procedure and a apparatus according to the preamble of claims 1 and 10.

The objective of the present invention is to propose a procedure for the selection and feeding of products, which ensure that flow interruptions or any other are avoided jamming of the products being fed, regardless of the shape and dimensions thereof.

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Another objective of the present invention is to propose a method characterized by particularly simple operating steps, which do not require complicated and / or expensive devices to carry them

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A further objective of the present invention is provide an apparatus capable of preventing any jamming and / or obstruction of the channels that feed the products above, regardless of their form and dimensions.

Still another objective of this invention is to propose an apparatus that guarantees high levels of reliability and productivity in any operating condition without modifying the functionality of the unit in any way complete.

The objectives indicated above are achieved according to the content of the claims.

The features are described below. characteristics of the present invention, where they are described some preferred but not limiting embodiments, with reference to the attached drawings, in which:

- Figures 1, 2, 3 are side views schematics of an apparatus capable of carrying out the procedure proposed, in corresponding operating stages particularly significant.

- Figure 4 is a side view of the apparatus proposed in accordance with another embodiment.

- Figures 5a and 5b are side views and magnified from a particularly significant part of the apparatus of Figure 4 in two technical-functional aspects particularly significant.

With reference to the drawings above indicated, numerical reference 5 indicates, by way of example, a band of blister packs transported in a medium of transport of known type (not shown) in one direction to front W. It will be understood that the invention described later in this report, as well as all the considerations raised then they also apply to product packaging in bottles or boxes or in other similar containers, with the condition that the procedure and feeding apparatus used are the same or very similar to those described.

In order to better understand the procedure of The present invention is considered to be described first place an apparatus to carry out the procedure.

With reference to the attached drawings, the numeral general reference 1 indicates an apparatus for selection and supply of products 2 to a band of blister packs 5, device designed to carry out the procedure proposed by the invention.

The apparatus 1 includes a first hopper 3, which Contains 2 unselected products in large quantities, and with the objective of feeding the input sections 30a of a plurality of first channels 30, which are substantially parallel and in adjoining arrangement.

The unselected products contained in the first hopper 3 are not classified and some of them The required nominal size of each product may not be adjusted. It is evident that in the case that the actual dimensions of a product contained in the first hopper are less than nominal dimensions, said product will not cause any problem during the packing procedure, in particular not It will get stuck inside the feed channels. TO Then, products of similar size, or products calibrated, indicate both products whose dimensions are perfectly fit the required size as the products whose  Dimensions are slightly smaller than required.

On the contrary, when the dimensions of product are greater than nominal, the feed channel it may get clogged easily or the product may not even enter the channel, thus interrupting the flow of Feeding and filling operation of blister packs.

Then the products of unequal size 20, or non-calibrated products, will in fact refer only to products that have dimensions larger than required

Therefore, entry section 30a of the first channel presents a cross section gradually decreasing, that is, it forms a conical entry section and the narrower cross section will be equal to the nominal section of the feed channels 30, which allows the passage, one by one, of only products of similar size 2 *, that is to say products whose dimensions are equal or slightly smaller than nominal dimensions.

Typically, the passage of size products similar through each first channel 30 is due, for example, to the severity (figure 1).

Therefore, older products dimensions are retained within the input sections 30a, evidently also stopping the feed flow of products.

A series of valves 6 are connected each to the corresponding input section 30a, for example in hinge with it, of the first 30 channels in order to eliminate from them the products of unequal size 20, which clog entry sections 30a and therefore can be retained inside the channels (figure 3).

Conical inlet section 30a and valves related 3 together form the selection means 6, which they must remove uncalibrated products 20 before they are transported to the first 30 channels, and send them to a collection container 8.

It turns out that only size products similar, or products with smaller dimensions, can pass through the first channels 30. The first channels 30 feed a second hopper 4, which contains only the calibrated products 2 * in large quantities, that is, products that conform to nominal size required.

Channels 30 are provided only by way of example. In fact, they could be more advantageously replaced with a ramp, not shown, located immediately below the opening of exit of the conical sections of entrance 30a and that lead to a second hopper 4.

This is because there is no need to maintain the products in rows between the first and second hoppers, but only on the initial road, when they are transported through of the conical input sections to be selected.

The second hopper 4 feeds the sections of input 40a of a plurality of second channels 40, substantially parallel and arranged in contiguity, through which all 2 * products contained in the second hopper 4 they can pass one by one, for example by gravity.

Each of the second channels 40 feeds the corresponding longitudinal row of blister packs 50 (figures 1, 2, 3).

Because the second hopper 4 is filled only with products of similar size 2 *, it will not be produced no traffic jam in the path between the second hopper and the Blister pack band or other container.

It follows that the flow of products from the second hopper until the blister pack band takes place evenly, without any interruption, and that all of the blister packs are filled with the respective products or the bottles / boxes with the expected quantity of products.

For the operation of the selection means 6, that is the valves that cooperate with the conical sections of input, each first channel 30 is provided with a sensor 7, which is located below the selection means 6 and which detects the interruption of the flow of products of similar size 2 * inside the first channel 30. When this happens, they do operate the selection means 6 so that these eliminate from the input sections 30a of the first channel 30, the products of uneven size 20, which obstruct it (see figure 2).

In accordance with the above, the sensor 7 cooperates with selection means 6 to restore the continuous and regular flow of products of similar size 2 * through of the first channel 30.

Advantageously, each input section 30a can equipped with a sensor 7, which operates the respective valves 6.

Alternatively, a device (not shown) associated with the selection means 6 above, to run all cyclically the valves 6, so that they are removed from each inlet section 30a products of unequal size 20, which possibly obstruct the input sections and therefore are retained within thereof, and to maintain substantially continuous flow and regular of products of similar size 2 * through the first respective channels 30. This last variation indicated corresponds particularly to the case in which channels 30 are replace with a ramp, in which case sensor 7 would result difficult to assemble In addition, in the latter case it would also result more difficult to detect the interruption of the flow of products from each entry section 30a due to the absence of rows of Products immediately below.

With reference to Figures 4, 5a and 5b, of according to another embodiment of the selection means, the first hopper 3 feeds the inlet sections 30a of the first channels 30 by means of a vibrating conveyor belt substantially horizontal linear 31, which transports the products 2 to a selector 32, which is tilted and leads to entrance sections 30a.

In the latter case, the selection means 6 is advantageously formed by tubular parts 35 that are joined in hinge to the input sections 30a of each first channel 30 and whose dimensions are similar to those of said first channel in As for the step section.

Near entrance sections 30a and more above the tubular portions 35, there is a first means of rotation 33, for example a brush, associated with selector 32.

The brush 33 retains, with respect to the direction of movement F1 (figure 5a), products 2 that are not they find correctly oriented and they do not enter the parts tubular 35, thus maintaining in the input sections 30a a single layer of product feed 2, which then they are introduced in the first channels 30.

In addition, it prevents size products unequal 20 enter the tubular parts 35 or, if they enter all ways in them, that are stuck and retained at one point intermediate of said tubular parts 35. More generally, as can be seen in figure 5a, the size products slightly larger than the nominal size are retained near the inlet opening of the tubular parts and remain retained in that position.

In order to help carry out those actions, the tubular parts 35 may also have a conical cross section.

The tubular parts 35 are joined in hinge so that they rotate between a normal setting of operation A, in which they remain aligned with the first channels 30, sending the flow of products to them, and a discharge configuration B, in which the tubular parts 35 no longer are aligned with the first channels 30 respective.

An ejection means 36 is located near the input sections 30a of the first channels 30, so that it interacts with the respective tubular parts 35 when they are in download configuration B, so entering the tubular part, preferably from the side of exit, extracting the products located in it.

Advantageously, the ejection means 36, preferably operated by pneumatic cylinders, it catches the tubular part 35 in coaxial orientation with it (figure 5b).

Therefore, the products stuck inside the tubular parts 35 or located opposite the entrance of the tubular parts 35, which do not have the size required, they are unloaded in the collection container 8.

During the time interval corresponding to the extraction of products of unequal size 20 of the parts tubular 35, that is, in the time corresponding to the movement of the tubular parts 35 between the normal configuration of operation A and download configuration B, and again at normal operating configuration A, all of the 2 products from the first conveyor belt linear vibratory 31 are transported indifferently to the collection container 8. With the condition that the brush is sufficiently rigid, products 2 transported by the first linear vibrating conveyor belt 31 prevents continue moving and fall into the collection container. When the tubular parts move back to their normal operating configuration A, the bristles of the brush are fold and rub the upper surface of the tubular parts 35, maintaining in this way its normal operation.

The tubular portions 35 of each first channel 30 and the ejection means 36 associated therewith can be made function separately or together simultaneously by a single order.

In the case of a separate operation of each ejection means 36, the corresponding tubular parts 35 they are also operated separately and selectively at receive the appropriate order from the corresponding sensor 7, associated with the same, as in the case of the embodiment described in first place.

In the case of the joint operation of the medium pneumatic ejection 36, also all parts tubular 35 is operated together by a single order between normal operating configuration A and the download configuration B and vice versa.

Only in the case where all of the tubular parts 35 are operated together and travel to the discharge configuration B, should the supply be interrupted from the first hopper 3 to the first linear vibrating conveyor belt 31, so that limit the number of products 2 transported to the collection container
8.

Still with reference to the embodiment proposed in figures 4, 5a and 5b, the second hopper 4 feeds the input sections 40a of the second channels 40 by means of a second linear vibrating conveyor belt substantially horizontal 41, which transports the products of 2 * similar size up to an inclined charger 42 that leads to input sections 40a.

Because the second hopper 4 is located Fill only with products of similar size 2 *, not produced no obstruction in the path between the second hopper and the blister pack band. It follows that the flow of products from the second hopper to the blister pack band takes place uniformly, without any interruption, and that the all blister packs are filled with the respective products.

Near entrance sections 40a, the magazine 42 is provided with a second rotation means 43, located on top of it substantially similar to the first medium of rotation 33, for example a brush.

Brush 43 retains, with respect to the F2 forward motion direction, size products similar 2 * that are not correctly oriented with with respect to the input sections 40a, thus maintaining near the input sections 40a a single feed layer of 2 * products, which are introduced in the second channels 40.

In addition, in the latter case, the first channels 30 can be replaced by a ramp, which preferably provides automatic cyclic operation of the means of selection, as in the first embodiment indicated previously.

For both embodiments described above, the following must be indicated.

In order to ensure the presence of a minimum amount of products of similar size 2 * inside the second hopper 4, taking into account statistical absences in the feeding them due to the obstruction of one or more input sections 30a of the first channels 30, or due to operation of the tubular parts 35 when they travel to the discharge configuration B, the flow rate of the products 2 by the first channels 30 it is higher than the flow rate of 2 * similar size products for the second 40 channels, of so that a continuous feed of each row is obtained Blister pack longitudinal 50 of band 5.

Either way, in order to keep in at all times a minimum level of products calibrated 2 * in the inside the second hopper 4, the latter is equipped with suitable detectors of known type (not shown), which are located near the bottom of the hopper, and they can supply a signal of minimum level alarm.

Similarly, in order to guarantee a correct operation of the proposed apparatus 1, the second hopper 4 it can be equipped with suitable detectors of known type (also not shown), which define a maximum level of calibrated products 2 * inside the second hopper 4, acting on the feeding of the first channels 30.

The operation of the apparatus 1, which performs the proposed procedure, described below, from a operating condition, in which the products of size similar 2 * pass through the first 30 channels and the means of  Selection 6 are inactivated.

When the sensors 7, connected to a first channel 30, detect the interruption of the flow of products 2 in the inside of it, due to the retention of a product of size different 20 retained inside one of the sections of entry 30a, operate the relevant selection means 6, in such a way that they remove the obstruction that has caused the interruption of product flow 2.

The operation of the selection means 6 allows to extract from the corresponding input section 30a, the products of unequal size 20 that obstruct the passage and send them to the collection container 8, thus restoring the flow of 2 * calibrated products inside the first channel involved.

In this way, each first channel 30 results crossed only by products of similar size 2 *, which accumulate in the second hopper 4, located below said channel.

The 2 * calibrated products present in the second hopper 4 are introduced, without causing any jamming or obstruction, inside the second channels 40 in order to continuously feed the blister packs in the rows corresponding lengths of blister packs 50 of the band 5.

From the previous description of the device, the proposed procedure for the selection and feeding of products to a band of blister packs 5 can be understood with ease.

The procedure substantially includes the following operating stages:

-

 The products 2, contained in the first hopper 3, are fed to the selection means, through which only the products of similar size 2 * may pass one by one (figure 1).

-

 The products of unequal size 20, that is, the products that have dimensions larger than the dimensions that allow the product passes through said first channels 30, as well as through the second channels 40, they are retained inside said selection means 6.

-

 The products of unequal size stuck 20 and retained within selection means 6 are extracted therefrom, restoring from this way the normal flow condition for the products.

-

 Be feed a second hopper 4 only with size products similar 2 *.

-

 The products of similar size 2 *, contained in the second hopper 4 are feed inputs 40a of a plurality of second channels 40, intended to allow 2 * calibrated products to pass one by one, feeding the blister packs of each row longitudinal blister packs 50 located below the second respective channel 40.

In summary, the procedure provides a online distribution operation of defective products by using the negative effect due to the products Defects themselves.

According to the procedure, the products that would not pass freely through the feed channels and not they would enter the blister packs or not fill in properly any other relevant vessel, are caught by selection means due to its different dimensions and They are then extracted from the flow of products.

The selection means can be formed, such as indicated in the device description, with input sections conical 30a and associated valves, or balancing tubular parts 35

Products of unequal size 20 extracted from the inlet sections 30a or the tubular parts 35 result advantageously transported to a collection container 8 (figure 3). Because they are inevitably also extracted 2 * similar size products from the 30th and inlet sections the tubular parts 35 together with the products of unequal size 20, are removed from the collection container and then recycle

The extraction of the products stuck in the inlet sections 30a or in the tubular portions 35, which of this way they block them, stopping the feed flow of products, can be performed as a result of an operation of flow check carried out on the flow of the 2 * calibrated products that pass through each first channel 30

The sensors 7 detect the interruption of the flow on channels 30 and then operate means of ejection to extract uncalibrated products 20, which obstruct the entrance sections 30a and that would also obstruct the first channels 30, in order to restore the continuous and regular flow of said products calibrated 2 * for each first channel 30 (figure 2).

Otherwise, it is possible to extract cyclically uncalibrated products 20, which could have clogged input sections 30a, in order to restore the continuous and regular flow of products calibrated 2 * for each first channel 30, in those cases where the flow results disrupted. This is preferable when the first channels They are replaced with a ramp that leads to the second hopper.

In order to guarantee a minimum amount of 2 * calibrated products inside the second hopper 4, taking into account the statistical absence of food at same due to the obstruction of the first channels 30, the feeding the first 30 channels provides a rate of product flow 2 higher than the product flow rate of similar size 2 *, carried out by the second channels 40, in a way that guarantees a continuous feeding of products to the blister packs 50 of the band 5 or the containers.

Products 2, 2 *, 20 taken into consideration may include pills, capsules and tablets for use pharmaceutical, although preferably for use similar to the pharmaceutical or for food use.

The proposed procedure for selection and feeding products to a band of blister packs results particularly suitable for processing any type of products and is extremely suitable for products food, similar to gums, for example chewing gum and Candies, etc.

The sequence of operating steps results particularly simple and does not require complicated devices and / or expensive The device guarantees a perfect filling of each package blister with only one product, thus avoiding any interruption of the feed flow of the products, regardless of their shape and dimensions.

The proposed apparatus for carrying out the procedure proposed by the present invention, guarantees high levels of reliability and productivity under any working condition

The selection means near the first channels, advantageously located near the entrance sections and cyclically operated or in response to sensors, extract the uncalibrated products, ie products of unequal size that obstruct the entrance sections, thus guaranteeing a substantially continuous and regular flow of products calibrated, ie of products of similar size, to the second hopper.

It is also indicated that the number of elements of the apparatus proposed by the present invention is limited and which are easy to produce, which advantageously reduces dimensions and production costs that are therefore They keep low.

Claims (27)

1. Procedure for the selection and feeding of products to blister packs or containers, from a main hopper (4) full of products (2), the procedure being characterized in that it includes the following: provide an auxiliary hopper (3) full of unselected products (2); feeding said main hopper (4) with products obtained from said auxiliary hopper (3) through means of selection (6) that retain products of unequal size (twenty); extract from said selection means (6) the products of unequal size (20), which are retained in the themselves, in order to restore a regular feed flow of products; feed said containers with products of similar size (2 *) contained in said main hopper (4). Method according to claim 1, characterized in that the products of unequal size (20) that pass through the selection means (6) are retained therein due to the conical section (30a) of said selection means, of so that they retain said products of unequal size (20). Method according to claim 2, characterized in that the products of unequal size (20) retained inside said conical section (30a) of said selection means are extracted therefrom by means of valves (6) connected in hinge with the conical section (30a) that are operated to open. Method according to claim 1, characterized in that the products of unequal size (20) that pass through the selection means (6) are retained due to the interception carried out by tubular parts (35) of said selection means which have an internal section equal to the nominal size of the products, so that said products of unequal size (20) are retained. Method according to claim 4, characterized in that the products of unequal size (20) retained by said tubular parts (6) of said selection means are extracted therefrom by balancing said tubular parts downwards. Method according to any one of claims 1 to 5, characterized in that it includes checking the continuity of the flow of products (2 *) into the first channels (30) connected to said selection means and operating said means of operation. selection (6) upon detecting that the flow has been interrupted, in order to extract products of unequal size (20) and restore a continuous flow of products of similar size (2 *) through said first channels (30). Method according to any one of claims 1 to 5, characterized in that it includes the cyclic operation of said selection means (6) in order to extract the products of unequal size (20) possibly retained within them, or by said means selection (6) maintain a continuous flow of products of similar size (2 *). Method according to any one of claims 1 to 7, characterized in that said selection means (6) are fed at a higher product flow rate than the flow rate of products of similar size fed to said second channel (40) , so that the accumulation of products of similar size (2 *) in said second hopper (4) is allowed and the continuous feeding of products to blister packs or containers is allowed. Method according to any one of claims 1 to 8, characterized in that the products extracted from said selection means (6) are collected in a collection container (8) to be classified and recycled. 10. Apparatus for the selection and feeding of products to blister packs or containers from a main hopper (4) filled with products (2), the apparatus being characterized in that it includes the following: an auxiliary hopper (3), which contains products not  selected (2) and the feeding of said main hopper (4); Y selection means (6) located between said auxiliary hopper (3) and said main hopper (4) to retain and extract products of unequal size (20), so that main hopper (4) contains only products of similar size (2 *) for feeding said blister packs or containers 11. Apparatus according to claim 10, characterized in that at least a first channel (30) is connected to said selection means (6) and leads to said main hopper (4). 12. Apparatus according to claim 11, characterized in that it includes a sensor (7), located below said selection means (6) for detecting the continuity of product flow (2 *) into said first channel ( 30) and to operate said selection means (6), so that products of unequal size (20) retained therein or near it are extracted. 13. Apparatus according to claim 10, characterized in that a ramp is connected to said selection means (6), leading to said main hopper (4). 14. An apparatus according to any of claims 10 to 13, characterized in that said selection means (6) are operated cyclically in order to extract products of unequal size (20) possibly retained therein or near them, and in order to restore the continuous flow of products of similar size (2 *). 15. Apparatus according to any of claims 10 to 14, characterized in that it includes, below said auxiliary hopper (3), a first linear vibrating conveyor belt (31) for feeding products (2) to a selector (32), which is substantially inclined and which leads to said selection means. 16. Apparatus according to any of claims 10 to 15, characterized in that said selection means (6) include at least one tubular part (35), whose internal dimensions are equal to the nominal dimensions of the products, said tubular part being movable (35) between a normal operating configuration (A), in which the flow of products is allowed, and a discharge configuration (B), in which the tubular part (35) is rotated, discharging products of unequal size (20) retained inside it or at its entrance side. 17. Apparatus according to claim 16, characterized in that it includes an ejection means (36) that interacts with said tubular part (35) when it is in a discharge configuration (B), from the outlet side, so that the products present inside it or retained on its input side. 18. Apparatus according to claim 16 or claim 17, characterized in that it includes a rotating means of brush type (33), connected to said tubular parts (35) and located above them, to retain, with respect to the direction of movement towards front (F1), unselected products (2) that are not correctly oriented with respect to said tubular parts (35) during the normal feeding of the products, thus maintaining a single feeding layer of the products (2) a said tubular parts. 19. Apparatus according to claim 18, characterized in that, when the tubular parts (35) are in their discharge configuration (B), said first rotating brush-like means (33) prevents said unselected products (2) from moving further and be extracted. 20. Apparatus according to any of claims 15 to 19, characterized in that it includes, below said second hopper (4), a second substantially horizontal linear vibrating conveyor belt (41) for feeding products of similar size (2 *) to a loader (42), substantially inclined and leading to said second channels (40). 21. Apparatus according to claim 20, characterized in that it includes a second rotating means of brush type (43) connected to said magazine (42) and located above it, to retain with respect to the direction of forward movement (F2), products of similar size (2 *) that are not correctly oriented with respect to said second channels (40), thus keeping close to the latter a single feed layer of products of similar size (2 *) input to said second channels (40). 22. Apparatus according to claim 17, characterized in that said ejection means (36) is operated by pneumatic cylinders. 23. Apparatus according to any of claims 10 to 13, characterized in that said selection means (6) include at least one conical inlet section (30a) and a valve connected to said conical inlet section (30a), said valve opening to unload products stuck and retained inside said conical entrance section (30a). 24. Apparatus according to any of claims 10 to 23, characterized in that it includes a plurality of substantially parallel and contiguous second channels (40), fed by said main hopper (4), for feeding products of similar size (2 *) to said blister packs or containers. 25. Apparatus according to any of claims 10 to 23, characterized in that it includes a plurality of first channels (30) substantially parallel and contiguous, fed by said auxiliary hopper (3) and leading to said main hopper, and a plurality of seconds channels (40) substantially parallel and contiguous, fed by said main hopper (4), for feeding products of similar size (2 *) to said blister packs or containers. 26. Apparatus according to any of claims 10 to 25, characterized in that the flow rate of unselected products (2) fed to said selection means (6) is higher than the flow rate of products of similar size (2 * ) fed to said blister packs or containers, so that said products of similar size (2 *) are allowed to accumulate inside said main hopper (4). 27. An apparatus according to any of claims 10 to 26, characterized in that, when the selection means (6) are operated, the discharged products are sent to a collection container (8).